hehe..Skip food for 4 weeks and pick up the GTX 295.
Actually, scratch that. Keep the 9600GT. Infiltration is still the only game worth playing.
I read that the GTX 295 is problematic for ARMA2. Don't ask for links because i can't remember. But anyway that's why i'll most probably go for the 285.
The 4890 ATI card offers the same or better performance in ARMA, according to the benchmark link found on the previous page, but i've had not so good experiences with ATI range cards overall.